1. Field of the Invention
The present invention relates generally to a digital interface, and more particularly to a method of controlling connection between nodes in a digital interface.
2. Description of the Related Art
FIG. 1 illustrates a connection state of a conventional 1394 system connected between nodes. Referring to FIG. 1, the conventional digital interface includes first and second input plug control registers 21 and 22 for inputting/outputting connection information between nodes connected to a 1394 serial bus 10 in accordance with control signals of an application node (not illustrated), a first audio/video node 20 comprising a first input master plug register 23, a third input plug control register 31 for inputting/outputting connection information between nodes connected to the 1394 serial bus 10 in accordance with control signals of the application node, a second audio/video node 30 comprising a second input master plug register 32, a fourth input plug control register 41 for inputting/outputting connection information between nodes connected to the 1394 serial bus 10 in accordance with control signals of the application node, a third video/audio node 40 comprising a third input master plug register 42, fifth and sixth plug control registers 51 and 52 for inputting/outputting connection information between nodes connected to the 1394 serial bus 10 in accordance with control signals of the application node, a fourth audio/video node 50 comprising a fourth input master plug register 53, an output plug control register 61 for inputting/outputting connection information between nodes connected to the 1394 serial bus 10 in accordance with control signals of the application node, and a fifth audio/video node 60 comprising an output master plug register 62.
The method of controlling connection between nodes for the conventional digital interface as constructed above will be explained in detail with reference to accompanying drawings.
The application node is allocated with a channel for transmitting isochronous data from the fifth audio/video node 60 to the first audio/video node 20 through a point-to-point connection or broadcast connection, and writes in the same format the output plug control register in the fifth audio/video node 60 and the input plug control register in the first audio/video node 20 in the output plug control register 61 and the second input plug control register 22.
Thereafter, the application node writes “1” in an on-line bit of the output plug control register 61 in the fifth audio/video node 60 and an on-line bit of the second input plug control register 22 to transmit the isochronous data.
Also, the application node writes in the same format the output plug control register in a point-to-point connection counter or a broadcast connection counter of the output plug control register 61 in the fifth audio/video node 60.
Then, the isochronous data is transmitted from the fifth audio/video node 60 to the first audio/video node 20 through the channel.
Thus, transmission of the isochronous data from the fifth audio/video node 60 to the second and fourth audio/video nodes 30 and 40 is performed through the above-described process.
According to the conventional method of controlling connection between nodes in a digital interface, however, since no command for connection the nodes to the digital interface is provided, the transmission/reception, reproduction and control of a data stream of a predetermined program cannot be smoothly performed.